One-pot synthesis of 3-(2-cyanophenyl)quinazolin-4(3H)-one

Anthranilonitrile reacting with formic acid at room temperature for three days gave 64% of 3-(2-cyanophenyl)quinazolin-4(3H)-one. Under similar conditions anthranilic acid. 4-nitroaniline, and 2,5-dichloroaniline were N-formylated in good yields.Institute of Organic Chemistry and Technology, Silesian Technical University, Krzywoustego, 4, 44–100 Gliwice, Poland; e-mail: wojtex@zeus.polsl.gliwice.pl. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 922–924, July, 2000.     

3,4-二氢-1-(4-哌啶基)-2(1H)-喹啉酮的合成

以苄胺为原料,经6步反应得到新型抗高血压药OPC-21268的中间体3,4-二氢-1-(4-哌啶基)-2(1H)-喹啉酮,总收率13．9％．     

Synthesis and Crystal Structure of a New Quinazolinone Compound 2,3-Dihydro-2-（2-hydroxyphenyl）-3-phenyl-quinazolin-4（1H）-one

A new quinazolinone compound 2,3-dihydro-2-(2-hydroxyphenyl)-3-phenylquinazolin-4(IH)-one 3 ([C2oH16O2N2]-C2H5OH, Mr = 362.42) and compound 2-(2-hydroxybenzylidene-amino)-N-phenyl-benzamide 2 (C2oH16O2N2, Mr = 316.34) were prepared from a precursor of 2-amino-N-phenyl-benzamide 1 (C13H12ON2, Mr = 212.25). Compound 3 was characterized by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic,space group Pbca with a = 1.2889(11), b = 1.6170(14), c = 1.7729(15) nm, V= 3.695(6) nm^3, Z= 8, F(000) = 1536, Mr = 362.42, Dc = 1.303 g/cm^3, μ(MoKa) = 0.087 mm^-1, R = 0.0447 and wR= 0.0879. The crystal structure analysis indicates that the title compound has a two-dimensional network structure formed by hydrogen bonds and electrostatic interactions.     

Synthesis, Crystal Structure and Antibacterial Activity of 1-（（2-Chloroquinolin-3-yl）-methyl）-pyridin-2（1H）-one

On the basis of the interesting structures and biological activities exhibited by several heterocyclic systems possessing the pyridone nucleus such as mappcine and camptothecin, we have planed to design the synthesis, crystal studies and antibacterial activity of the new 1-((2- chloroquinolin-3yl)-methyl)-pyridine-2(1H)-one building block. An X-ray analysis has provided valuable insight into the effect of steric factors on the three-dimensional shape of this compound which serves as a useful advanced intermediate in the synthesis of these biologically active molecules. A multistep synthesis of camptothecin (5) has been designed by retrosynthetic analysis as part of an ongoing program on lead anticancer drug.     

Synthesis of 3-[4-(1-Benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one Derivatives as Biological Agents

A protocol for the synthesis of 3-[4-(1-benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one derivatives (5a–e) has been developed from 1-(1-benzofuran-2-yl)-2-bromoethanone (2),which served as a key intermediate for the synthesis of the title compounds. The reaction of compound 2 with thiourea furnished 4-(1-benzofuran-2-yl)-1,3-thiazol-2-amine 3, which upon further reaction with various aromatic aldehydes, gave Schiff bases 4a–e. These Schiff bases, when treated with thioacetic acid in the presence of catalytic amount of anhydrous ZnCl₂, yielded thiazolidinone derivatives 5a–e. All the newly synthesized compounds have been characterized by analytical and spectral data and screened for their antimicrobial and analgesic activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis ofN-substituted 2-(5,6,7,8-tetrafluoro-4-oxo-1,4-dihydroquinolin-3-yl)glyoxylic acids

Methods for the synthesis of the earlier unknownN-substituted 2-(5,6,7,8-tetrafluoro-4-oxo-1,4-dihydroquinolin-3-yl)glycoxylic acids their esters from copper chelate of ethyl pentafluorobenzoylpyruvate were developed. The structure of intermediate ethyl 4-(R-amino)-2-oxo-3-pentafluorobenzoylbut-3-enoates is discussed. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1234–1239, July, 2000.     

Synthesis of Some 2-(3-Alkyl/aryl-5-trifluoromethylpyrazol-1-yl)-4-(coumarin-3-yl)thiazoles as Novel Antibacterial Agents

Abstract

Herein, we describe a one-pot synthesis of some novel 2-(3-alkyl/aryl-5-trifluoromethylpyrazol-1-yl)-4-(coumarin-3-yl)thiazoles (6) involving the reaction of 3-alkyl/aryl-5-hydroxy-5-trifluoromethyl-4,5-dihydropyrazole-1-thiocarboxamides (3) with 3-bromoacetylcoumarins (5) in the presence of sodium carbonate in ethanol. Reaction of 3 with 5 in the absence of sodium carbonate, however, resulted in the formation of 2-(3-alkyl/aryl-5-hydroxy-5-trifluoromethyl-4,5-dihydropyrazol-1-yl)-4-(coumarin-3-yl)thiazoles, which were subsequently dehydrated to 6 by refluxing in ethanol in the presence of sodium carbonate. The structure of the synthesized compounds (6) was confirmed by infrared (IR), mass, ¹H NMR, and ¹³C NMR spectra and elemental analysis data. Newly synthesized compounds (6) showed moderate to good activity against Gram-positive bacteria.     

Synthesis of Novel 2-(4-Oxo-3,4- Dihydroquinazolin-2-Ylsulfinylmethyl)-3H-Quinazolin-4-One

Abstract

Condensation of 2-mercapto-3H-quinazolin-4-one (1) with chloroacetic acid gave 4-oxo-3,4-dihydroquinazoline-2-yl-sulfanyl)-acetic acid (2) that with anthranilamide (3) gave 2-(4-oxo-3,4-dihydroquinazolin-2-ylsulfanylmethyl)-3H-quinazolin-4-one (4). Oxidation of 4 with sodium hypochlorite in alkaline medium gave the novel product, 2-(4-oxo-3,4- dihydroquinazolin-2-ylsulfinyl methyl)-3H -quinazolin-4-one) (5). The entire sequences of reactions in this work have been carried out using eco-friendly solvents and green conditions.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis of （S）-2-（3-Arylacrylamido）-3-{4-[2-（5-methyl-2-phenyloxazol-4-yl）ethoxy]phenyl}propanoic Acids

The synthesis of （S）-2-（3-arylacrylamido）-3-{4-[2-（5-methyl-2-phenyloxazol-4-yl）etho- xy]phenyl}propanoic acids is described. Their structures were confirmed by ^1H-NMR.     

Synthesis and Crystal Structure of Ethyl 3-（4-Chlorophenyl）-3,4-dihydro-6-methyl-4-oxo-2- （pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate

The crystal structure of the title compound ethyl 3-（4-chlorophenyl）-3,4-dihydro-6- methyl-4-oxo-2-（pyrrolidin-1-yl）furo[2,3-d]pyrimidine-5-carboxylate （C20H20ClN3O4, Mr= 401.84） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215（9）, b = 8.5311（4）, c = 21.6886（9） A^°, β = 91.607（1）°, V = 3814.0（3）A^°^3, Z = 8, Dc = 1.400 g/cm^3, F（000） = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.     

N-(3,4-二氢-2H-1-苯并吡喃-4)异硫脲类化合物的合成及其血管舒张活性

根据苯并吡喃类钾通道开放剂的作用机理和构效关系, 设计合成了13个苯并吡喃-4-异硫脲衍生物, 其结构经IR, ¹H NMR, MS和元素分析确证. 大鼠体外血管扩张实验研究表明, 多数化合物在1×10^－5 mol•L^－1 浓度下对30 mmol•L^－1 KCl诱导的大鼠主动脉条收缩具有一定程度的抑制作用, 其中化合物6l的血管收缩抑制活性较强.     

One-Pot Synthesis of Novel 2-(Thiazol-2-yl)-4,5-dihydropyridazin-3(2H)-one Derivatives Catalyzed by Activated KSF

A series of 2-(thiazol-2-yl)-4,5-dihydropyridazin-3(2H)-one derivatives were synthesized by one-pot multicomponent cyclocondensation of ketoacid, thiosemicarbazide, and phenacyl bromide using catalytical amount of KSF in EtOH under reflux. The straightforward synthesis, presence of two important class of heterocyclic rings in the individual molecule, easy workup of the products, rapid reaction, mild conditions, and good to excellent yields are notable features of this protocol.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Novel Approach for the Synthesis of N-Substituted-4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyramides

A simple and convenient method for the synthesis of N-substituted-4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyramides has been reported. Several aromatic and aliphatic amide derivatives of 4-(2-methyl-4-oxo-4H-quinazolin-3-yl)-butyric acid were prepared in 60–81% yields by refluxing it with different phosphazo compounds in toluene for approximately 1 h.     

A study of the Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one derivatives

Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement     

The Synthesis of 3-(2'-Hydroxybutyl) isobenzofuran-1 (3H)-one

l（3H】．Isobenzoturans（Dhthalldes】werereDortedtoexhibitawiderangeofbiologicalactivities．Forexample,3－n－butylphthallde（NB）exhibitsantlasthmatlc’,antlconvuls－ant“actlvltles．PenEandZhouhavestudiedonthemetabolismofNBPInrats‘．Theyfoundthat...     

Stripping voltammetric determination of silver(I) at carbon paste electrode modified with 3-amino-2-mercapto quinazolin-4(3H)-one

A differential pulse anodic stripping voltammetric method was developed for the determination of Ag(I) at a 3-amino-2-mercapto quinazolin-4(3H)-one modified carbon paste electrode. The analysis procedure consisted of an open circuit accumulation step in stirred sample solution for 12 min. This was followed by medium exchange to a clean solution where the accumulated Ag(I) was reduced for 15 s in −0.6 V. Subsequently an anodic potential scan was effected from −0.2 to +0.2 V to obtain the voltammetric peak. The detection limit of silver(I) was 0.4 μg L⁻¹ and R.S.D. for 10, 100 and 200 μg L⁻¹ silver(I) were 2.4, 1.8 and 1.3%, respectively. The calibration curve was linear for 0.9-300 μg L⁻¹ silver(I). Many coexisting ions had little or no effect on the determination of silver(I). The procedure was applied to determination of silver(I) in X-ray photographic films and natural waters. In X-ray photographic film samples, the results have compared to those obtained by atomic absorption spectroscopy.     

Synthesis and Crystal Structure of （Z）-1- （3-Fluorobenzyl）-5-（（3-fluorobenzylimino）（2-hydroxy-4-methoxyphenyl）methyl）pyridin-2（1H）-one

The title compound （Z）-1-（3-fluorobenzyl）-5-（（3-fluorobenzylimino）（2-hydroxy-4- methoxyphenyl）methyl）pyridin-2（1H）-one （C27H22F2N2O3,Mr = 460.47） was synthesized and crystallized. The crystal belongs to the triclinic system,space group P1 with a = 9.951（6）,b = 10.059（6）,c = 12.927（7）A,α = 109.828（7）,β = 102.304（7）,γ = 104.898（7）°,Z = 2,V = 1110.2（11）A^3,Dc =1.377 Mg/m^3,μ（MoKα） = 0.102 mm^-1,F（000） = 480,the final R = 0.0449 and Rw = 0.1250 for 4595 observed reflections （I 〉 2σ（I））. X-ray analysis reveals that both m-fluorobenzyl groups are diorientationally disordered because of the rotation of C–C single bond which was represented as F（1）,F（2） and F（1＇）,F（2＇）. The diorientational disorder was refined and gave the occupancies of 0.665（4） and 0.335（4） for F（1） and F（1＇）,0.631（3） and 0.369（3） for F（2） and F（2＇）. Hydrogen bonds existing in the cell link different components to stabilize the crystal structure. The active data proved that the title compound has good anti-HBV activity.     

合成3-羟基-2-(4-吡啶基)-1H-茚-1-酮的工艺改进

以邻苯二甲酸酐和4-甲基吡啶为起始原料,正十二烷为溶剂,氯化锌为催化剂,于190℃反应24 h合成了抗癌药物瓦他拉尼的关键中间体——3-羟基-2-(4-吡啶基)-1H-茚-1-酮,收率90.6%,其结构经1H NMR,IR和MS确证。     

Synthesis and reactions of 2-hydroxy-4-oxo-4-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-but-2-enoic acid methyl ester

2-Hydroxy-4-oxo-4-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-but-2-enoic acid methyl ester (1) was synthesized by the reaction of pentafluoroacetophenone with dimethyl oxalate in the presence of sodium methylate. Subsequently, reactions of compound 1 with aniline, o-phenylenediamine, and o-aminophenol were investigated. In addition, the thermal cyclization of ester 1 was studied and led to the formation of 5,6,8-trifluoro-7-methoxy-4-oxo-4H-chromene-2-carboxylic acid methyl ester (6) due to nucleophilic substitution of the 3-fluoro group. Hydrolysis of compound 1 and subsequent cyclization by treatment with SOCl₂ gave 5-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-furan-2,3-dione (3). Thermal decarbonylation of compound 3 under mild conditions resulted in the formation of 3-(2,3,5,6-tetrafluoro-4-methoxyphenyl)-propene-1,3-dione (4) which dimerized to pyranone 5.     

Synthesis and Characterization of Novel 2-(1,2,3-Triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles and 2-(4,5-Dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles

Reactions of 1-(5-methyl)-1H-1,2,3-triazol-4-yl)ethan-1-ones and benzaldehydes in ethanol under basic conditions gave the corresponding chalcones. Reactions of the chalcones combined with thiosemicarbazide in dry ethanol containing sodium hydroxide afforded the corresponding pyrazolin-N-thioamides. Reactions of the synthesized pyrazolin-N-thioamides and several ketones (namely, ethyl 2-chloro-3-oxobutanoate, 2-bromoacetylbenzofuran, and hydrazonoyl chloride) gave the corresponding novel 2-(1,2,3-triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles in high yields (77–90%). Additionally, 2-(4,5-dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles were obtained in high yields (84–87%) from reactions with N-pyrazoline-thioamides and 4-bromoacetyl-1,2,3-triazoles under basic conditions. The structures of six of the newly synthesized heterocycles were confirmed by X-ray crystallography.